Kolby is a distinctive girls' name in United States, ranking #7009 in 2005 with 17 recorded births. The name reached its all-time peak in 2000 with 55 births ranking #2690. Since 1996, the popularity has decreased by 57.5%. In 2005, approximately 1 in every 108,688 girls born was named Kolby. STABLE Recent data shows the name is currently stable.